Cylinder lock



1954 ANTONIO JUAN MIR ETAL 2,687,640

CYLINDER LOCK Filed Oct. 25, 1952 KR mmmw w JM M 0 T 00A 0 w W HHE f A W OWW mp w QMNM AG A Y B Patented Aug. 31, 1954 UNITED STATES PATENT OFFICE- CYLINDER LOCK Antonio Juan Mir, Enrique Juan Mir, Aldo Ferro Pastor, and Giraldo Ferro Pastor, Havana, Cuba Application October 25, 1952. Serial No. 316,926

Claims. 1

This invention relates to improvements in pickproof locks of the type known as rotatable barrel locks, and of the type described in our Patent No. 2,596,720 dated May 13, 1952. In this type of lock a lock body has rotatably mounted therein a barrel which can be rotated only with the proper key. But such locks have been known to be picked rather easily by experts and it is the purpose of this invention to either completely prevent the lock from being picked, or at least make it most difficult to accomplish this feat. There are numerous methods to pick such locks, and this invention intends to make it almost impossible for all of such methods, either using the feeling system with instruments, or using instruments alone.

It is therefore the purpose of this invention to provide a barrel type lock with tumbler pins of a special construction. Such pins or tumblers are spring urged downward and are in accordance with this invention made of three parts. The main top-pin adjacent to the spring is provided with a reduced section at its lower end, which presses upon a disk. This disk being of a smaller diameter than the bore, permits the disk to move freely within the bore thus making the picking of the lock practically impossible, especially when the feel system is used, as there is no assurance of the radial location of the disk.

It is another object of this invention to provide the holes in the barrel for the lower pins with a tapered counterbore. Looks at times stick, because the sharp edge of the bore in the barrel may be very slightly out of alinement with the bore of the upper pins, thus preventing these pins from readily dropping into the lower bore, creating a situation where fumbling with the key and lock becomes necessary.

Various further and more specific objects, features and advantages will clearly appear from the detailed description given below taken in connection with the accompanying drawings which form a part of this specification and illustrate merely by way of example certain embodiments of the device of the invention.

The invention consists in such novel features, arrangements and combinations of parts as may be shown and described in connection with the lock herein disclosed by way of example only and as illustrative of preferred embodiments.

In the following description and in the claims, parts will be identified by specific names for convenience, but such names are intended to be as generic in their application to similar parts as the art will permit. Like reference characters denote like parts in the several figures of the drawing.

Referring now to the drawing:

Fig. 1 is a longitudinal section through the shell and the barrel of the lock, showing the locking elements according to the. invention, in locked position.

Fig. 2 is a cross section on the line Z-2 of Fig. 1;

Fig. 3 is a view similar to Fig. l, but showing the proper key inserted in the lock, for opening the lock;

Fig. 4 is a view similar to Fig. 2, but with the barrel displaced after a futile attempt to pick the lock;

Fig. 5 is a perspective view of the barrel removed from the lock;

Fig. 6 is a view similar to Fig. 5, but showing the barrel in a modified form; and

Fig. 7 is an enlarged fragmentary view of the barrel, housing, and corresponding moving parts for illustrative purpose.

Referring now to the drawings and more particularly to Figs. 1 to 5- inclusive, there is shown a cylindrical barrel 5, having the conventional key slot 9, the barrel 5, being rotatably seated in a shell 6. Radial bores la in the shell 6 are normally aligned with similar bores 2a. in the barrel 5 to form channels within which tumbler pins 2 and driver pins I are displaceable. Each driver pin I terminates at its end facing the associated tumbler pin in a section or point 4. of reduced diameter, this pin bearing upon a spacer or disk 3 which separates the pins I, 2 from each other and which is of a smaller diameter from that of these pins. It is important to note that the disks 3 are connected with neither the driver pins I nor the tumbler pins 2. Springs I, lodged in the bores Ia bear upon the drivers I in the well known manner, thereby normally causing these drivers partially to protrude into the bores 2a of the barrel so as to lock the latter against rotation relative to the shell 6; this position being illustrated in Figs. 1 and 2.

When the proper legitimate or mating key 8 (Fig. 2) is introduced into the slot 9, the tumblers 2 are raised until the drivers I together with their reduced sections or points 4 as well as the disks 3 are entirely received in the bores Ia, the upper edges of the tumblers being then flush with the periphery of the barrel 5; this enables the barrel to be rotated freely inside the shell 6 permitting the release of the lock.

As best seen in Fig. 5, each of the bores 2a of the barrel 5 has at its upper end countersunk at Zband is flanked by two relatively shallow grooves I0 extending over a limited arc of the periphery of the barrel, the depth of these grooves increasing toward their extremities remote from the bore 2 w. These extremities form sharp steps or ab-utments II, best seen in Figs. 2 and 4, adapted to come to rest against the points 4 of the pins I if the corresponding tumblers were raised only to the position shown in Fig. 4 (with the top of disk 3, rather than of pin 2, flush with the periphery of the barrel). If, therefore, an intruder tries to pick the lock in the manner previously described, the barrel ,5 will start to yield, and rotate, as soon as the top understood that the grooves I must have a width less than the diameter of disks 3 so that the disks 3 will be unable to enter them after insertion of the key 8 has enabled an authorized person to displace the barrel 5 from its normal position.

Fig. 6 shows a modified barrel 5a wherein the grooves I0 have been replaced by a'pair of longitudinal grooves [0a extending on both sides of the row of bores 2a, the points 4 of the pins l drop-ping into one or the other of these grooves when the barrel is rotated after an attempt to pick the lock.

Fig. 7 illustrates in enlarged form a fragmentary portion of the lock showing the relation. between the pins, disks and the bores. Figs. 1 to 7, inclusive, illustrated a countersunk portion 21) of the bore 2m in the barrel 5. Referring especially to Figs. 1 and 2, it can be seen clearly how the countersunk portion will facilitate the entrance of the disk 3 and the pins I, into the bores 2a of the barrel 5.

The disk 3 is clearly shown as having a diameter less than the bore 2a, pin I, or pin 2, that is, with a space 3a around its edge and between the latter and the internal wall of the bore 2a. Thus, disk 3 is free to slidably move from side to side or tipped at the top of pin 2, thereby making it extremely diflicult to feel or fish around the lock because of the haphazard, unpredictable or uncertain movability, of the disk 3 when an unauthorized person attempts to pick the lock.

As heretofore stated, each of the bores 2a of barrel 5 is countersunk as indicated at 2b performing the function of a guide for facilitating the reception of disks 3 and pins I within the bores 2a.

It is understood that the recesses or grooves [0 may commence at a short distance from the bores 2a, rather than commencing at the said bores 10.

Although we have described our improvements with considerable detail and with respect to certain particular forms of our invention, we do not desire to be limited to such details since many changes and modifications in the form, arrangements, proportions and sizes thereof may well be made without departing from the spirit and scope of our invention in its broadest aspect.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent, is:

1. In a lock having a shell and a cylindrical barrel rotatable in said shell, the barrel having a longitudinal slot adapted to receive a key; a. set of radial bores in said barrel communicating with said slot, each of said bores being enlarged at its upper end, a set of radial bores in said shell, the bores of said two sets being aligned in a predetermined position of said barrel, the aligned bores forming a set of channels, an elongated tumbler element in the part of each channel adjacent said slot, spring means in the part of each channel remote from said slot, and looking means in each channel positioned between said tumbler element and said spring means and urged by said spring means toward said slot, each of said locking means including a driver element nearest said spring means, a spacer element nearest said tumbler element, said spacer element being less in diameter than said channel and fitting loosely inside said channel, and an intermediate element of reduced section between said driver element and said spacer element, said spacer element being independent of said tumbler element and of said intermediate and driver elements, said barrel being provided with recesses angularly displaced from the bores thereof and adapted to receive said intermediate elements, said recesses limiting rotation of said barrel relative to said shell by co-operation with said intermediate elements upon partial displacement of said tumbler elements against the action of said spring means by introduction into said slot of an instrument other than a mating key, said spacer elements being large enough to pass over said recesses without substantial hindrance upon rotation of said barrel following insertion of the proper key.

2. A lock according to claim 1 wherein said spacer element is a disk of lesser diameter than said channel.

3. A lock according to claim 1 wherein said intermediate element forms part of said driver element, the length of said intermediate element being greater than the depth of said recesses at a point remotest from the bores of said barrel.

4. In a lock having a shell and a cylindrical barrel in said shell, said barrel having a longitudinal slot adapted to receive a key and further having a radial bore communicating with said slot, said shell having a radial bore aligned with said barrel radial bore in a predetermined angular position of said barrel, thereby forming a continuous channel therewith, the combination, with a tumbler pin in the part of said channel adjacent said slot, of locking means in the part of said channel remote from said slot and spring means urging said locking means into contact with said tumbler pin and the latter toward said slot, said locking means including a driver element nearest said spring means, a spacer element nearest said tumbler pin, said spacer element being less in diameter than said channel, said driver element having a projection of reduced section contactable with said spacer element, said spacer element being independent of said tumbler pin and of said driver element, said barrel being recessed adjacent said first bore, thereby forming an abutment angularly displaced from said first bore and adapted to limit rotation of said barrel relative to said shell by engagement of said projection upon displacement of said tumbler pin against the action of said spring means, said spacer element being large enough to pass over said recess without substantial hindrance upon displacement of said tumbler pin suflicient to position the outer end of the latter flush with the periphery of said barrel.

5. A lock according to claim 4 wherein said recess extends circumferentially of said barrel and gradually deepens on passing from said first bore toward said abutment.

References Cited in the file of this patent UNITED STATES PATENTS Pastor et al May 13, 1952 

